SACRAMENTO -- Firefighters lit a Christmas tree during a controlled burn demonstration, and within 10 seconds, the flames had reached the ceiling and smoke quickly filled the home.
The point of Thursday's exercise was to show how quickly fire can spread.
When it starts at the bottom of the tree, it's at about 300 to 500 degrees and it ignites. When it gets to the top of a flashover fire, it can get anywhere from 900 to 1100 degrees.
Here are the dangers according to Metro Fire -- unwatered Christmas trees, candles near holiday decorations or near space heaters,
trees next to fireplaces and overloading electrical systems.
"They are kicking on their heating and ventilation systems, which might have dust collecting in them, and when that dust gets hot that can combust," said Sac Metro Fire Captain Chris Vestal.
More people die from smoke inhalation than actual burns.
Firefighters are also pushing the "close before you doze" campaign. Closing your door at night can save your life during a house fire.
"In a room with an open door, a bedroom with an open door where somebody is sleeping, you can have about 10,000 parts per million of carbon monoxide. In a room where the door is shut approximately only about 1,000 parts per million of carbon monoxide and greatly reduced temperatures," Vestal said.
And it will increase your chances of surviving a fire.
The goal for Metro Fire this holiday season is for families to put safety first.